Answer:
1 mole of ferric contains 2 moles of iron,and 12 moles of oxygen atoms, and three moles of sulphate ions
Answer is: the percent by mass of NaHCO₃ is 2,43%.
m(NaHCO₃) = 10 g.
V(H₂O) = 400 ml.
d(H₂O) = 1 g/ml.
m(H₂O) = V(H₂O) · d(H₂O).
m(H₂O) = 400 ml · 1 g/ml.
m(H₂O) = 400 g.
m(solution) = m(H₂O) + m(NaHCO₃).
m(solution) = 400 g + 10 g.
m(solution) = 410 g.
ω(NaHCO₃) = 10 g ÷ 410 g · 100%.
ω(NaHCO₃) = 2,43 %
SI unites are based on multiplying or dividing by 10, 100, 1,000, 10,000 (and so on...) depending on the unit you're solving for.
Answer:
option D is correct
Explanation:
no of moles in 3 grams of HCL=3/36=0.08
if 1 mole of HCL require 1 mole of NaOH then 0.08 moles required 0.08 moles of NaOH
mass of 0.08 moles of NaOH=moles*molar mass=0.08*40=3.2 grams
so 3 grams are required in the reaction